The liquid crystal display with a compact body, power saving, no radiation and many other advantages, has been widely application. Most of the liquid crystal display in the market is a backlight type liquid crystal display, the backlight type liquid crystal display includes a liquid crystal panel and a backlight module. The working principle of the liquid crystal display is placing liquid crystal molecules in two parallel glass substrates, and applying driving voltage to control the direction of rotation of the molecule the liquid crystal between the two glass substrates to reflect the light from the backlight module to produce an image.
Wherein, thin film transistor-liquid crystal display (TFT-LCD) has gradually dominated the display field due to its low power consumption, excellent picture quality and high production yield. The similarly, the thin film transistor liquid crystal display includes a liquid crystal panel and a backlight module, and the liquid crystal panel includes a color filter substrate (CF substrate, also known as a color filter substrate) and a thin film transistor substrate (TFT substrate) and a transparent electrode is present on the inner side of the substrate. Between the two substrates, a layer of liquid crystal molecules (liquid crystal, LC). Liquid crystal panel is controlled by the electric field on the orientation of liquid crystal molecules, changing the polarization state of light, and through the polarizing plate to achieve the optical path of the penetration and blocking, to achieve the purpose of display.
The conventional TFT substrate is formed on a substrate with a semiconductor layer, typically an n-type semiconductor, such as amorphous silicon or polysilicon. Wherein, the electron mobility of polysilicon is higher than that of amorphous silicon. However, as the demand for the display panel increases, the electron mobility of the polysilicon can no longer show the demand for the device.